An amino acid-based gelator for injectable and multi-responsive hydrogel

Hydrogels formed by gelators have attracted growing attention for their promising application in biomaterials and biotechnology. We describe in this paper the generation and characterization of a novel photo-, thermal-and p H-responsive hydrogel based on an amino acid gelator AA-Azo-EG;. Specifically,the gelator bears an amino acid head, an azobenzene（Azo） linker, and a short oligoethylene glycol tail（EG;）. The resulting AA-Azo-EG;hydrogel is injectable and exhibits interesting helical self-assembled structures. Meanwhile, the hydrogel is able to experience a gel-sol or gel-precipitate phase transition responding to external stimuli. Thus, this AA-Azo-EG;gelator is a promising building block for intelligent materials and drug delivery.